MODIS Land Data Formats and Access MODIS Science

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MODIS Land Data Formats and Access MODIS Science Team Meeting (Land Discipline Breakout Session)

MODIS Land Data Formats and Access MODIS Science Team Meeting (Land Discipline Breakout Session) July 13, 2004 Robert Wolfe Raytheon ITSS @ NASA GSFC Code 922 July 12, 2004 - Wolfe - MODLAND Mtng.

Land Algorithm Dependency Input Data Previous Period’s Calibrated Radiance Geolocation Fields Cloud Mask Aerosol

Land Algorithm Dependency Input Data Previous Period’s Calibrated Radiance Geolocation Fields Cloud Mask Aerosol Precipitable Water DAO Data BRDF/Albedo Land Surface Temp. /Emissivity Land Cover L 2/L 2 G Products Snow/Sea-Ice Cover Land Surface Temp. /Emissivity Surface Reflectance Fire Grid Pointer Data Grid Angular Data Previous L 3/L 4 Products Snow/Sea-ice Cover Surface Reflectance Land Surface Temp. /Emissivity Fire and Burned Areas Vegetation Indexes BRDF/Albedo LAI/FPAR GPP/NPP Land Cover and Vegetation Dynamics Vegetation Cover Change and Continuous Fields Evapotranspiration July 12, 2004 - Wolfe - MODLAND Mtng. 3

Product Format • Hierarchical Data Format (HDF) – Self describing file format • Science

Product Format • Hierarchical Data Format (HDF) – Self describing file format • Science Data Sets (SDSs) – 2 D, 3 D or 4 D arrays – Bit Fields – unsigned integers broken into groups of bits – Discrete values – e. g. , Snow, Cloud, etc. – Scaled Integers – valid range, scale and offset included • Attributes – text or other data that annotates the file (global) or arrays (SDSs) • Metadata – ECS metadata for products (stored as attributes) – includes QA information, date/time products acquired/produced, etc. • . met file contains the ECS core metadata – some additional fields – some fields (QA, etc. ) may be updated when product distributed • HDF-EOS Metadata (SWATH or GRID) – geometric information that relates data to specific earth locations July 12, 2004 - Wolfe - MODLAND Mtng. 4

Level 2 Products • Retrieved geophysical parameters at the same location and in the

Level 2 Products • Retrieved geophysical parameters at the same location and in the same format as the MODIS Level 1 instrument data – 288 granules/day; 5 min. ; approx. 2340 x 2030 km – 250 m, 500 m and 1 km nadir resolutions July 12, 2004 - Wolfe - MODLAND Mtng. 5

Level 2 G, 3 and 4 Products (fine resolution) Sinusoidal • Level 2 G/3:

Level 2 G, 3 and 4 Products (fine resolution) Sinusoidal • Level 2 G/3: earth-gridded geophysical parameters • Level 4: earth-gridded model outputs • Daily, 8 -day, 16 -day, 32 -day, monthly and yearly products • Fine resolution grid(s) – 10º x 10º Tiles: – Sinusoidal (equatorial); 7. 5, 15 and 30 arcsec. resolution (roughly 250 m, 500 m and 1 km) – LAEA (sea-ice products, polar projection) Lambert Azimuthal Equal Area (LAEA) July 12, 2004 - Wolfe - MODLAND Mtng. 6

Climate modeling grid products • Resolution: 0. 05º (now) and 0. 25º (previous) degrees

Climate modeling grid products • Resolution: 0. 05º (now) and 0. 25º (previous) degrees • Almost all products are lat/long – sea-ice is current exception – in polar grid (snow in C 5) July 12, 2004 - Wolfe - MODLAND Mtng. (from BU – NBAR CMG – days 193 -208, 2001) 7

MODIS products per day @ 1 X* Produced by Product Generation Executives Volume GB/day

MODIS products per day @ 1 X* Produced by Product Generation Executives Volume GB/day Files/day Level 0 EDOS N/A 67 12 Level 1+ GES DAAC MODAPS 6 DAAC 2 MODAPS 235 4, 500 2, 400 Atmos 2, 950 Oceans Type Oceans SST, Atmospheres MODAPS 16 18 Atmos 80 SST Land MODAPS 27 330 9, 500 Snow/Sea Ice MODAPS 9 12 2, 300 60 742 24, 600 Totals * Sustained processing rate is currently 6 X (4 X for reprocessing + 1 X forward Terra + 1 X forward Aqua) July 12, 2004 - Wolfe - MODLAND Mtng. 8

Getting MODIS Data • Order from DAAC through EOS Data Gateway – response is

Getting MODIS Data • Order from DAAC through EOS Data Gateway – response is a few hours – services (e. g. subsetting) available for some products • Get data from DAAC data pools – most recently produced data are online and available via FTP • Get data from other sources (Science team sites, MODIS Rapid Response, direct broadcast, etc. ) July 12, 2004 - Wolfe - MODLAND Mtng. DAAC Unique Ordering Interfaces 9

MODIS Data Distribution • MODIS DAACs distribute more than 1. 3 TB/day of MODIS

MODIS Data Distribution • MODIS DAACs distribute more than 1. 3 TB/day of MODIS standard products – about 130, 000 product files/day – Land products distributed from EDC and NSIDC DAACs are about 1/3 of the total • Science team and other non-DAAC distribution (rapid response) add an additional 0. 1 TB/day July 12, 2004 - Wolfe - MODLAND Mtng. 10

DAAC distribution services • Subsetting via. EDG (through HEW Subsetting Appliance) – Only implemented

DAAC distribution services • Subsetting via. EDG (through HEW Subsetting Appliance) – Only implemented at NSIDC – all products (except CMGs) • Service for products in Data Pools using HEG – Spatial and parameter subsetting • NSIDC: all product except CMGs • EDC LP: phased release – some product already released – Compression – Gzip, Zip, Unix compression (. gz, . zip, . z) – Format conversion • NSIDC: L 2 products currently (L 2 swath); other products soon • EDC all products (as released) – Newly installed ECS version 6 A. 07 system has capability to stage data through data pools – so users “should” be able to apply Compression and Format Conversion by first ordering the data using EDG and then performing the services before downloading data • USGS seamless distribution system (spatial and parameter subsetting, compression and format conversion) – currently only 500 m 16 -day VI/EVI (MOD 13 A 2 for 2000 to 2003) • Data mining script for data pools (MODextract) – works for L 3 tiles for user specified date range – finds and downloads data automatically July 12, 2004 - Wolfe - MODLAND Mtng. 11

DAAC developed/supported user tools • MODIS Reprojection Tools (EDC LP DAAC) – both grid

DAAC developed/supported user tools • MODIS Reprojection Tools (EDC LP DAAC) – both grid and swath (new) – reprojection (resampling) – also: spatial subsetting, parameter subsetting, mosaics and format conversion • LDOPE tools (EDC LP DAAC) – (see Roy’s slides) July 12, 2004 - Wolfe - MODLAND Mtng. 12

Other tools http: //hdfeos. gsfc. nasa. gov/hdfeos HDF-EOS Tools User Forum can be useful

Other tools http: //hdfeos. gsfc. nasa. gov/hdfeos HDF-EOS Tools User Forum can be useful for new EOS data users (same site) July 12, 2004 - Wolfe - MODLAND Mtng. 13